241 research outputs found
Autologous fibrin sealant (Vivostat®) in the neurosurgical practice: Part I: Intracranial surgical procedure
Background: Hemorrhages, cerebrospinal fluid (CSF) fistula and infections are the most challenging postoperative complications in Neurosurgery. In this study, we report our preliminary results using a fully autologous fibrin sealant agent, the Vivostat® system, in achieving hemostasis and CSF leakage repair during cranio-cerebral procedures. Methods: From January 2012 to March 2014, 77 patients were studied prospectively and data were collected and analyzed. Autologous fibrin sealant, taken from patient's blood, was prepared with the Vivostat® system and applied on the resection bed or above the dura mater to achieve hemostasis and dural sealing. The surgical technique, time to bleeding control and associated complications were recorded. Results: A total of 79 neurosurgical procedures have been performed on 77 patients. In the majority of cases (98%) the same autologous fbrin glue provided rapid hemostasis and dural sealing. No patient developed allergic reactions or systemic complications in association with its application. There were no cases of cerebral hematoma, swelling, infection, or epileptic seizures after surgery whether in the immediate or in late period follow-up. Conclusions: In this preliminary study, the easy and direct application of autologous fibrin sealant agent helped in controlling cerebral bleeding and in providing prompt and efficient dural sealing with resolution of CSF leaks. Although the use of autologous fibrin glue seems to be safe, easy, and effective, further investigations are strongly recommended to quantify real advantages and potential limitations
I.B.S. coatings on large substrates: Towards an improvement of the mechanical and optical performances
présenté par A. RemillieuxLarge mirrors (350 mm), having extremely low optical loss (absorption, scattering, wavefront) were coated for the VIRGO interferometer. The new mirror generation needs better wavefront and lower mechanical loss. The first results are discussed
Titania-doped tantala/silica coatings for gravitational-wave detection
Reducing thermal noise from optical coatings is crucial to reaching the required sensitivity in next generation interferometric gravitational-wave detectors. Here we show that adding TiO2 to Ta2O5 in Ta2O5/SiO2 coatings reduces the internal friction and in addition present data confirming it reduces thermal noise. We also show that TiO2-doped Ta2O5/SiO2 coatings are close to satisfying the optical absorption requirements of second generation gravitational-wave detectors
Original optical metrologies of large components
présentée par A. RemillieuxThe coating deposition on large optical components (diameter 350 mm) has required the development of new metrology tools at 1064 nm. To give realistic values of the optical performances, the whole surface of the component needs to be scanned. Our scatterometer (commercial system) has been upgraded to support large and heavy samples. The other metrology tools are prototypes we have developed. We can mention the absorption (photothermal effect) and birefringence bench, a control interferometer equipped with an original stitching option, the optical profilometer (RMS roughness and small defect measurements). A detailed description of these metrology benches will be exposed. Their sensitivity, accuracy and capability to map the optical properties of substrates or mirrors will be discussed. We will describe the recent developments: the stitching option adapted to the Micromap profilometer to measure the RMS roughness on larger area (exploration of a new spatial frequency domain), the accurate bulk absorption calibration
Ventricular-vascular coupling in hypertension: methodological considerations and clinical implications
The present review is addressed to analyse the complex interplay between left ventricle and arterial tree in hypertension. The different methodological approaches to the analysis of ventricular vascular coupling in the time and frequency domain are discussed. Moreover, the role of hypertension-related changes of arterial structure and function (stiffness and wave reflection) on arterial load and how ventricular-vascular coupling modulates the process of left ventricular adaptation to hypertension are analysed.The different interplay between vascular bed and left ventricle emerges as the pathophysiological basis for the development of the multiple patterns of ventricular structural adaptation in hypertension and provides a pathway for the interpretation of systolic and diastolic functional abnormalities observed in hypertensive patients. Targeting the therapeutic approach to improve ventricular-vascular coupling may have relevant impact on reversing left ventricular hypertrophy and improving systolic and diastolic dysfunctio
When should cardiovascular prevention begin? The importance of antenatal, perinatal and primordial prevention
Cardiovascular diseases represent a major health problem, being one of the leading causes of morbidity and mortality worldwide. Therefore, in this scenario, cardiovascular prevention plays an essential role although it is difficult to establish when promoting and implementing preventive strategies. However, there is growing evidence that prevention should start even before birth, during pregnancy, aiming to avoid the onset of cardiovascular risk factors, since events that occur early in life have a great impact on the cardiovascular risk profile of an adult. The two pillars of this early preventive strategy are nutrition and physical exercise, together with prevention of cardio-metabolic diseases during pregnancy. This review attempts to gather the growing evidence of the benefits of antenatal, perinatal and primordial prevention, discussing also the possibility to reverse or to mitigate the cardiovascular profile developed in the initial stages of life. This could pave the way for future research, investigating the optimal time and duration of these preventing measures, their duration and maintenance in adulthood, and the most effective interventions according to the different age and guiding in the next years, the best clinical practice and the political strategies to cope with cardiovascular disease
Interventions to Optimize Spinal Cord Perfusion in Patients With Acute Traumatic Spinal Cord Injury: An Updated Systematic Review
STUDY DESIGN: Systematic review update.
OBJECTIVES: Interventions that aim to optimize spinal cord perfusion are thought to play an important role in minimizing secondary ischemic damage and improving outcomes in patients with acute traumatic spinal cord injuries (SCIs). However, exactly how to optimize spinal cord perfusion and enhance neurologic recovery remains controversial. We performed an update of a recent systematic review (Evaniew et al, J. Neurotrauma 2020) to evaluate the effects of Mean Arterial Pressure (MAP) support or Spinal Cord Perfusion Pressure (SCPP) support on neurological recovery and rates of adverse events among patients with acute traumatic SCI.
METHODS: We searched PubMed/MEDLINE, EMBASE and ClinicalTrials.gov for new published reports. Two reviewers independently screened articles, extracted data, and evaluated risk of bias. We implemented the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach to rate confidence in the quality of the evidence.
RESULTS: From 569 potentially relevant new citations since 2019, we identified 9 new studies for inclusion, which were combined with 19 studies from a prior review to give a total of 28 studies. According to low or very low quality evidence, the effect of MAP support on neurological recovery is uncertain, and increased SCPP may be associated with improved neurological recovery. Both approaches may involve risks for specific adverse events, but the importance of these adverse events to patients remains unclear. Very low quality evidence failed to yield reliable guidance about particular monitoring techniques, perfusion ranges, pharmacological agents, or durations of treatment.
CONCLUSIONS: This update provides an evidence base to support the development of a new clinical practice guideline for the hemodynamic management of patients with acute traumatic SCI. While avoidance of hypotension and maintenance of spinal cord perfusion are important principles in the management of an acute SCI, the literature does not provide high quality evidence in support of a particular protocol. Further prospective, controlled research studies with objective validated outcome assessments are required to examine interventions to optimize spinal cord perfusion in this setting
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